1. Field of the Invention
The invention relates to a scan method, and in particular to a scan method reducing the number of required detectors.
2. Description of the Related Art
FIG. 1a shows a conventional scanner 1, comprising a media detector A, a scan-in detector B, an image sensor 10, a weight 20 and a transmission mechanism 30. Transmission mechanism 30 comprises a pick arm 31, a roller 32, a roller 33 and a roller 34.
When scanner 1 scans, recording media passes between weight 20 and image sensor 10, and image sensor 10 captures image data therefrom.
With reference to FIG. 1b, media detector A detects whether recording media P is in a transmission position A1, and scanner 1 performs scan process by auto document feeder or flatbed according to the detection result. When recording media P actuates the media detector A, the pick arm 31 raises, allowing placement of recording media P into the scanner 1. During scanning, if the media detector A confirms the presence of recording media P in the transmission position A1, the scanner 1 continues the scan process.
With reference to FIG. 1c, scan-in detector B confirms a distance between recording media P and a scan position, the position of the recording media P (in or out of the scanner 1), and detects paper jam.
In conventional scanning, first, media detector A detects the presence of recording media P in transmission position A1. If present, transmission mechanism 30 transmits recording media P toward the image sensor 10. When recording media P actuates scan-in detector B, image sensor 10 scans the recording media P. Finally, when media detector A and the scan-in detector B detect no recording media P, the scanner 1 stops.
In conventional scanning, more then two detectors are required, increasing costs.
U.S. Pat. No. 5,844,698 discloses a scan method, however, only one sheet of recording media can be scanned in a single scan process rather then continuous scanning of a plurality of recording media, since paper jam is indistinguishable from lack of media altogether.